Abstract:
A semiconductor device includes a group of fin structures. The group of fin structures includes a conductive material and is formed by growing the conductive material in an opening of an oxide layer. The semiconductor device further includes a source region formed at one end of the group of fin structures, a drain region formed at an opposite end of the group of fin structures, and at least one gate.
Abstract:
A method of fabricating an integrated circuit with ultra-shallow source/drain junctions utilizes a solid-phase impurity source. The solid-phase impurity source can be a doped silicon dioxide layer approximately 300 nm thick. The structure is thermally annealed to drive dopants from the solid-phase impurity source into the source and drain regions. The dopants from the impurity source provide ultra-shallow source and drain extensions. The process can be utilized for P-channel or N-channel metal oxide field semiconductor effect transistors (MOSFETS).
Abstract:
A silicon-on-insulator substrate is disclosed which comprises: a silicon substrate layer; a first insulation layer over the silicon substrate layer; a conductive layer over the first insulation layer comprising at least one metal or metal silicide over the first insulation layer; a second insulation layer over the conductive layer; a silicon device layer comprising silicon over the second insulation layer; at least first conductive plug through the silicon substrate and the first insulation layer contacting the conductive layer; and at least one second conductive plug through the silicon device layer and the second insulation layer contacting the conductive layer. Also disclosed are methods for forming silicon-on-insulator substrates having improved stable ground characteristics.
Abstract:
A method of isolation of active islands on a silicon-on-insulator semiconductor device, comprising the steps of (a) providing a silicon-on-insulator semiconductor wafer having a silicon active layer, a dielectric isolation layer and a silicon substrate, in which the silicon active layer is formed on the dielectric isolation layer and the dielectric isolation layer is formed on the silicon substrate; (b) etching the silicon active layer to form an isolation trench wherein an unetched silicon layer at bottom of the isolation trench remains; (c) oxidizing the layer of silicon at the bottom of the isolation trench to a degree sufficient to oxidize through the layer of silicon at the bottom to the dielectric isolation layer; and (d) filling the isolation trench with a trench isolation material to form a shallow trench isolation structure.
Abstract:
In one embodiment, the present invention relates to a method of facilitating heat removal from a device layer of a silicon-on-insulator substrate comprising bulk silicon, an insulation layer over the bulk silicon, and a silicon device layer over the insulation layer involving forming at least one conductive plug comprising a conductive material within the bulk silicon and the insulation layer so as to contact the silicon device layer. In another embodiment, the present invention relates to a silicon-on-insulator structure, made of a silicon substrate layer; an insulation layer over the silicon substrate layer; a silicon device layer comprising silicon over the insulation layer; a conductive plug through the silicon substrate layer and the insulation layer contacting the silicon device layer; and a heat generating structure on the silicon device layer at least partially overlapping the conductive plug.
Abstract:
A field effect transistor (FET) is formed on a silicon substrate, with a nitride gate insulator layer being deposited on the substrate and an oxide gate insulator layer being deposited on the nitride layer to insulate a gate electrode from source and drain regions in the substrate. The gate material is then removed to establish a gate void, and spacers are deposited on the sides of the void such that only a portion of the oxide layer is covered by the spacers. Then, the unshielded portion of the oxide layer is removed, thus establishing a step between the oxide and nitride layers that overlays the source and drain extensions under the gate void to reduce subsequent capacitive coupling and charge carrier tunneling between the gate and the extensions. The spacers are removed and the gate void is refilled with gate electrode material.
Abstract:
STI (Shallow Trench Isolation) structures are fabricated such that leakage current is minimized through a field effect transistor fabricated between the STI structures. The shallow trench isolation structure include a pair of isolation trenches, with each isolation trench being etched through a semiconductor substrate. A first dielectric material fills the pair of isolation trenches and extends from the isolation trenches such that sidewalls of the first dielectric material filling the isolation trenches are exposed beyond the top of the semiconductor substrate. A second dielectric material is deposited on the sidewalls of the first dielectric material exposed beyond the top of the semiconductor substrate. The second dielectric material has a different etch rate in an acidic solution from the first dielectric material filling the isolation trenches. The present invention may be used to particular advantage when the first dielectric material filling up the isolation trenches is comprised of silicon dioxide, and when the second dielectric material deposited on the sidewalls of the first dielectric material is comprised of silicon nitride. With the protective silicon nitride covering the sidewalls of the silicon dioxide filling the STI (shallow trench isolation) trenches, formation of divots is avoided in the silicon dioxide filling the STI (shallow trench isolation) trenches. Thus, when a field effect transistor is fabricated between such STI structures, silicides formed near the STI structures do not extend down toward the junction of the drain contact region and the source contact region of the field effect transistor such that drain and source leakage current is minimized.
Abstract:
A method for fabricating short channel field effect transistors with dual gates and with a gate dielectric having a high dielectric constant. The field effect transistor is initially fabricated to have a sacrificial gate dielectric and a dummy gate electrode. Any fabrication process, such as an activation anneal or a salicidation anneal of the source and drain of the field effect transistor, using relatively high temperature is performed with the field effect transistor having the sacrificial gate dielectric and the dummy gate electrode. The dummy gate electrode and the sacrificial gate dielectric are etched from the field effect transistor to form a gate opening. A layer of dielectric with high dielectric constant is deposited on the side wall and the bottom wall of the gate opening, and amorphous gate electrode material, such as amorphous silicon, is deposited to fill the gate opening after the layer of dielectric has been deposited. Dual gates for both an N-channel field effect transistor and a P-channel field effect transistor are formed by doping the amorphous gate electrode material with an N-type dopant for an N-channel field effect transistor, and by doping the amorphous gate electrode material with a P-type dopant for a P-channel field effect transistor. The amorphous gate electrode material in the gate opening is then annealed at a relatively low temperature, such as 600.degree. Celsius, using a solid phase crystallization process to convert the amorphous gate electrode material, such as amorphous silicon, into polycrystalline gate electrode material, such as polycrystalline silicon. Thus, relatively low temperatures are used in the present invention to preserve the integrity of the gate dielectric having the high dielectric constant.
Abstract:
A semiconductor device and a method of making the device with a raised source/drain has a semiconductive material that is non-selectively deposited in a layer over the device area. The semiconductive material is then etched to form spacers that will form the raised soure/drain areas following doping of the spacers. The gate of the semiconductor device is protected during the etching by an etch stop layer that is grown or deposited over the structure to be protected, e.g., the gate, prior to the deposition of the semiconductive material layer. Lightly doped drain ion implantation is performed prior to the formation of the spacers, and source-drain ion implantation is performed preferably after the formation of the spacers, to create the shallow junctions.
Abstract:
Asymmetrically doped source/drain regions of a transistor are formed employing protective insulating layers to prevent a portion of the gate electrode from receiving an excessive impurity implantation dose and penetrating through the underlying gate insulating layer into the semiconductor substrate. Sidewall spacers are employed during heavy implantation.